The objective of the investigation proposed here is to complete the development of a dipstick for morphine in urine for use at addiction treatment centers. The prototype dipstick was developed under an NIH General Research Support Grant to GSRI. The dipstick test for morphine requires only two simple step procedures: (a) immersion of the dipstick in the urine for about 60 seconds, and (b) visualization of the morphine adsorbed to the dipstick surface by an appropriate chemical reaction. The dipstick test for morphine in urine should be highly useful because the test does not require a laboratory and can be run and read correctly by staff personnel at addiction treatment centers. Anyone who can distinguish colors and color changes will be able to perform the tests accurately. No knowledge of chemistry is needed. In addition, the dipstick test costs only pennies per test. Since the dipstick test could be completed immediately after the patient (addict) providing the urine specimen is present, direct confrontation with a positive dipstick test might elicit an immediate knowledge of drug use, and further confirmation tests might not be necessary. It can be computed that in excess of $20 million could be saved each year by application of dipstick tests at addiction treatment centers, because these type tests can be performed at a fraction of the costs associated with the usual laboratory screening procedures.